Saturday, October 24, 2009

A Beginner's Guide to Scanning Postcards

I was honored when Evelyn

1. What equipment should I use when scanning postcards?
A flatbed scanner that can scan at a 300 dots per inch (dpi) or greater resolution and can scan to the tagged image file (.tif) format is a must. Your computer should have photo editing software such as Adobe Photoshop, Corel Paint Shop Pro, or the many free types you can download from the Internet (do a Google search). Cotton gloves such as those found at your local photography supply store or online at archival supply websites are also vital for keeping your postcards from being microscopically damaged from the oils in your skin when handling.

2. On what settings should I put my scanner?
As mentioned above, you'll want to scan at no less than 300 dots per inch resolution. Many experts agree that 600 dpi is even better. This will enable you to zoom in and see details that your naked eye can miss, which is especially helpful for those postally used postcards with difficult-to-read postmarks! Also, it is imperative that you scan to a tagged image file (.tif) format (more on this later). All scanning should be done in full color, even for those photo postcards that are printed in black and white. The color will bring out the highlights and shadows that scanning in black and white and greyscale cannot do, and will also digitally preserve your postcard as it truly is viewed by the human eye: in color.

3. How do I prepare for scanning?
The glass plate of your scanner should never be cleaned by commercial glass cleaning products such as Windex, which may leave a chemical residue that can damage your postcards. Instead, use a soft lint-free cloth that has been sprayed with water to clean the glass plate of dust, oil, and streaks. Make sure the plate is completely dried before placing any postcard on its surface. I also like to tape a large piece of black construction paper to the inside of the white lid of my scanner, so that the edges of the postcard can easily be seen in the scanned image. Otherwise, the white edges of the postcard can seem to merge into the image of the white lid and it is difficult to tell exactly where they are when cropping the image.

Meanwhile, your postcards should be set up in scanning order on a nearby clean surface, free from any food, beverages, or other items that could damage them. Take the time to figure out exactly what you want to scan and in which order they will be scanned.

4. How should the postcards be scanned?
I scan four postcards at a time with spaces between them, being very careful not to slide them around on the glass (pick them up to move them). I then carefully flip each one over in its place and scan the reverse of the four as another image. This saves me time in scanning and room on my hard drive.

5. How do I save and use my scanned images?
Every image should be saved as a .tif file, which does not deteriorate over time with every use like .jpg files do. Jpg files are common photo file formats used to transport photos from one location (your hard drive, for example) to another (an online photo album, or an e-mail, for example). The problem here is that .jpg files are compressed for that easy transportation, and every time you save or use that file (e-mail it, download it, etc.), it loses some of its quality. Also, if you've ever zoomed in on a .jpg file, you'll notice that it quickly becomes blurry, whereas a .tif file can be enlarged multiple times in a zooming action before the resolution blurs.

When I make presentations about scanning and preservation, I like to do a little demonstration. I take a piece of blank paper and show it to my audience, saying, "This is my digital photo as a .jpg file." I then crumple the paper and toss it to a member of the audience and explain that because I crumpled (compressed) it, it made it easier for me to transport to someone else. Then I have the person smooth out the paper the best they can to look at it. Of course, now it's wrinkled. Then I have them crumple it again and toss it back to me. Each time the paper is used, it is crumpled and then unfolded. The quality deteriorates. The same thing happens at a digital level; the quality of the photograph in a .jpg file deteriorates every time it is accessed.

So even if your postcards are not photo postcards, they should still be saved as .tif files. This will digitally preserve the image. Any enhancements, cropping, color changes (color to black and white or greyscale, etc.) should be done to copies of the original .tif file. If you wish to e-mail a postcard image or upload it to a blog, do a "Save As" action and save the image as a .jpg (retaining the original .tif file, of course) and then send it out.

Lastly, I "separate" the images of the four postcards by copying each one four times and cropping them. I tag the images with information that will help me easily find them in a desktop search. These final two steps, separating and tagging are done after I've finished all my scanning.

6. What do I need to do when I'm finished scanning my postcards?
I recommend placing the postcards in an acid- and lignin-free storage container or enclosed display frame. Both Archival Products and Archival Suppliers offer postcard preservation supplies.

Never place them in "magnetic" photo albums or cheap photo display books. Don't store them with newspaper clippings, which are made of acidic paper. Also, don't store them with photographs, as the postcards may be made of acidic materials themselves and destroy the photographs stored with them. Acidic paper creates a gas that eats away at photographic materials.

Be sure to back up the scanned images to a DVD, flash drive, external hard drive, or the Internet. Have two different kinds of backups and store them in two places, one away from your home.

By following these tips, you can preserve, display, and share your wonderful postcard collection in a digital format. If you have further questions, leave them in the comments below. And be sure to join me and my family historian and family archivist friends for Scanfest, usually held the last Sunday of each month, here at AnceStories. There are a number of experts who would be glad to give scanning and preservation advice, and we have a lot of fun, too!


Gini said...

Great information and this post has helped me so much, thank you and congratulations!

Miriam Robbins said...

Thank you, Gini!

Anonymous said...


Good post! I find it helpful to use the "descreening" process when scanning postcards - especially older ones or "shiny" ones.


Miriam Robbins said...

Thanks for the additional tip, Donna. I'll have to check to see if I have that option on my scanner!

Judith Richards Shubert said...

Thank you, Miriam, for the wonderful advice. I plan to attend your Scanfest as my husband and I have been handed the job of scanning about 40 yearbooks from my high school. I'm having a little trouble with quality. I'm eager to learn more.

Miriam Robbins said...

Wow! That sounds like a massive task, Judith! I'm going to think on that and get back to you.

Sheila said...

I've just read your article and gone away to experiment with my scanner. I can increase the resolution to 600 (or more it seems) but I don't at the moment see a way to produce a .tif file. I'll have a look at some other software I have. A good way to while away a few happy hours this weekend! Thank you.

Postcardy said...

Descreening is necessary for printed postcards but is not necessary for real photo postcards.

Your tips are good for high quality images you may want to print or archive but are not necessary for display on the web. I only save a low resolution jpg image for my blog, using "save for web" in Photoshop. If I ever need a good image, I will do a new scan.

Miriam Robbins said...

Sheila, do a Google search for "free photo editing software" .tiff (with two Fs) to see if you can find something to help you. I have heard Gimp is pretty good, but haven't been able to open the website, lately.

Miriam Robbins said...

Hi, Postcardy,

You are right: you cannot display .tif(f) files on the web; they will not upload, as they are too large and online photo albums don't support them.

While you may feel .jpg files are adequate to scan your postcard collection, please consider the means of .tif files for preservation. Many of my readers are family historians and family archivists, and the postcards within their possession are not just valuable as antiques, but personally historic and sentimental. Their loss would be much more than their financial worth.

Fire, flooding, mold and mildew, insects, inadequate and improper storage, and theft (because thieves don't just steal things when they break in; they often randomly vandalize) all play into the loss of valuable collections. This is why it's important for us to create .tif files of our postcards, photographs, and documents for posterity; they will last longer than .jpg files and are a great substitute should something happen to the original.

Thank you for dropping by!

Christine said...

Very useful information.

Miriam Robbins said...

Thanks for dropping by, Christine!

Edward Hands said...

I'm sorry to say but your comments on deteriorating JPG files are incorrect and misleading. You can open and close a JPG file millions of times with no loss of quality. Quality is only lost when you resample or resize etc and then save it. Think about it, how can opening and closing a digital file change it at all?
best wishes
Edward Hands
London, England

Miriam Robbins said...

Edward, you are correct. It is when you save the file that it deteriorates. Thanks for the heads up; I will make the correction immediately!

Focus Grandma! FOCUS!! said...

Thank you for the really educational Blog. I have been hearing more and more about saving files as tiff files or is suppose to be tif? I have been saving the recent scanned pictures as tiff files, will have to rescan a lot and save them as tiff. I am usually saving 2 copies now. One tiff or the original and one jpg to use on the web or to send someone, unless they ask for a tiff file.

Unknown said...

Dorothy said. . .

Excellent suggestions! Thank you! Can you recommend a scanner that you particularly like for postcards? I have a MAC. I have 435 postcards to scan from 1905 to 1925. Most were written to my grandmother. I'd like to make permanent copies of them and the notes written on them, but I would also like to make a coffee table book of the images. I want to make sure they are properly scanned. Will using the advice you have given us give me the highest quality reproducible file for an art book?

Thanks again.